diff --git a/src/covjson_pydantic/coverage.py b/src/covjson_pydantic/coverage.py
index 013a45a..c43baaa 100644
--- a/src/covjson_pydantic/coverage.py
+++ b/src/covjson_pydantic/coverage.py
@@ -1,6 +1,10 @@
-from __future__ import annotations
+import sys
+
+if sys.version_info < (3, 9):
+    from typing_extensions import Annotated
+else:
+    from typing import Annotated
 
-from typing import Annotated
 from typing import Dict
 from typing import List
 from typing import Literal